Truncated channel state information feedback

ABSTRACT

This disclosure describes systems, methods, and devices related to truncated channel state information (CSI) feedback. A device may establish a communication link with a station device. The device may identify a feedback frame received from the station device, wherein the feedback frame comprises information associated with channel state information (CSI). The device may identify the feedback frame as one or more feedback samples.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims the benefit of U.S. Provisional Application No.63/309,198, filed Feb. 11, 2022, the disclosure of which is incorporatedherein by reference as if set forth in full.

TECHNICAL FIELD

This disclosure generally relates to systems and methods for wirelesscommunications and, more particularly, to truncated channel stateinformation (CSI) feedback.

BACKGROUND

Wireless devices are becoming widely prevalent and are increasinglyrequesting access to wireless channels. The Institute of Electrical andElectronics Engineers (IEEE) is developing one or more standards thatutilize Orthogonal Frequency-Division Multiple Access (OFDMA) in channelallocation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a network diagram illustrating an example network environmentfor truncated CSI feedback, in accordance with one or more exampleembodiments of the present disclosure.

FIGS. 1-5 depict illustrative schematic diagrams for truncated CSIfeedback, in accordance with one or more example embodiments of thepresent disclosure.

FIG. 6 illustrates a flow diagram of a process for an illustrativetruncated CSI feedback system, in accordance with one or more exampleembodiments of the present disclosure.

FIG. 7 illustrates a functional diagram of an exemplary communicationstation that may be suitable for use as a user device, in accordancewith one or more example embodiments of the present disclosure.

FIG. 8 illustrates a block diagram of an example machine upon which anyof one or more techniques (e.g., methods) may be performed, inaccordance with one or more example embodiments of the presentdisclosure.

FIG. 9 is a block diagram of a radio architecture in accordance withsome examples.

FIG. 10 illustrates an example front-end module circuitry for use in theradio architecture of FIG. 9 , in accordance with one or more exampleembodiments of the present disclosure.

FIG. 11 illustrates an example radio IC circuitry for use in the radioarchitecture of FIG. 9 , in accordance with one or more exampleembodiments of the present disclosure.

FIG. 12 illustrates an example baseband processing circuitry for use inthe radio architecture of FIG. 9 , in accordance with one or moreexample embodiments of the present disclosure.

DETAILED DESCRIPTION

The following description and the drawings sufficiently illustratespecific embodiments to enable those skilled in the art to practicethem. Other embodiments may incorporate structural, logical, electrical,process, algorithm, and other changes. Portions and features of someembodiments may be included in, or substituted for, those of otherembodiments. Embodiments set forth in the claims encompass all availableequivalents of those claims.

In the discussions of IEEE 802.11bf, the topic of channel stateinformation (CSI) report has been discussed. Channel state information(CSI) can refer to known channel properties of a communication link.This information describes how a signal propagates from the transmitterto the receiver and represents the combined effect of, for example,scattering, fading, and power decay with distance. The CSI can make itpossible to adapt transmissions to current channel conditions. Invarious embodiments, CSI information can be used for achievingcommunication with high data rates, for example, in multi-antennasystems. In one embodiment, a channel field (CEF) can be used formultiple-input and multiple-output (MIMO) channel estimation. In oneembodiment, the CEF fields may use Orthogonal Frequency-DivisionMultiple Access (OFDMA) modulation.

A scheme is proposed to reduce the feedback overhead without losing thesensing information of interest. It is proposed to feedback a truncatedtime-domain channel response for sensing applications. The scheme onlyfeeds back the channel response samples from delay 0 up to a delay thatcorresponds to a distance of interest, e.g., 20 m. For example, for an80 MHz channel sounding and the reflections within 20 m, only 5 samplesneed to be fed back. The delay of each multipath is right at thereceiver's sampling time such that the effect of the long tails of eachmultipath was not considered. This leads to inaccurate CSI feedback andsensing results.

Example embodiments of the present disclosure relate to systems,methods, and devices for truncated channel state information (CSI)feedback.

In one or more embodiments, a truncated CSI feedback system may feedback time-domain samples of the channel impulse response, which are inthe time interval containing most of the power of the channel impulseresponse. The interval not only contains the main peaks of the multipathbut the tails with significant power as well. A truncated CSI feedbacksystem may enhance the performance of WiFi sensing.

The above descriptions are for purposes of illustration and are notmeant to be limiting. Numerous other examples, configurations,processes, algorithms, etc., may exist, some of which are described ingreater detail below. Example embodiments will now be described withreference to the accompanying figures.

FIG. 1 is a network diagram illustrating an example network environmentof truncated CSI feedback, according to some example embodiments of thepresent disclosure. Wireless network 100 may include one or more userdevices 120 and one or more access points(s) (AP) 102, which maycommunicate in accordance with IEEE 802.11 communication standards. Theuser device(s) 120 may be mobile devices that are non-stationary (e.g.,not having fixed locations) or may be stationary devices.

In some embodiments, the user devices 120 and the AP 102 may include oneor more computer systems similar to that of the functional diagram ofFIG. 7 and/or the example machine/system of FIG. 8 .

One or more illustrative user device(s) 120 and/or AP(s) 102 may beoperable by one or more user(s) 110. It should be noted that anyaddressable unit may be a station (STA). An STA may take on multipledistinct characteristics, each of which shapes its function. Forexample, a single addressable unit might simultaneously be a portableSTA, a quality-of-service (QoS) STA, a dependent STA, and a hidden STA.One or more illustrative user device(s) 120 and the AP(s) 102 may beSTAs. One or more illustrative user device(s) 120 and/or AP(s) 102 mayoperate as a personal basic service set (PBSS) control point/accesspoint (PCP/AP). The user device(s) 120 (e.g., 124, 126, or 128) and/orAP(s) 102 may include any suitable processor-driven device including,but not limited to, a mobile device or a non-mobile, e.g., a staticdevice. For example, user device(s) 120 and/or AP(s) 102 may include, auser equipment (UE), a station (STA), an access point (AP), a softwareenabled AP (SoftAP), a personal computer (PC), a wearable wirelessdevice (e.g., bracelet, watch, glasses, ring, etc.), a desktop computer,a mobile computer, a laptop computer, an Ultrabook™ computer, a notebookcomputer, a tablet computer, a server computer, a handheld computer, ahandheld device, an internet of things (IoT) device, a sensor device, aPDA device, a handheld PDA device, an on-board device, an off-boarddevice, a hybrid device (e.g., combining cellular phone functionalitieswith PDA device functionalities), a consumer device, a vehicular device,a non-vehicular device, a mobile or portable device, a non-mobile ornon-portable device, a mobile phone, a cellular telephone, a PCS device,a PDA device which incorporates a wireless communication device, amobile or portable GPS device, a DVB device, a relatively smallcomputing device, a non-desktop computer, a “carry small live large”(CSLL) device, an ultra mobile device (UMD), an ultra mobile PC (UMPC),a mobile internet device (MID), an “origami” device or computing device,a device that supports dynamically composable computing (DCC), acontext-aware device, a video device, an audio device, an A/V device, aset-top-box (STB), a blu-ray disc (BD) player, a BD recorder, a digitalvideo disc (DVD) player, a high definition (HD) DVD player, a DVDrecorder, a HD DVD recorder, a personal video recorder (PVR), abroadcast HD receiver, a video source, an audio source, a video sink, anaudio sink, a stereo tuner, a broadcast radio receiver, a flat paneldisplay, a personal media player (PMP), a digital video camera (DVC), adigital audio player, a speaker, an audio receiver, an audio amplifier,a gaming device, a data source, a data sink, a digital still camera(DSC), a media player, a smartphone, a television, a music player, orthe like. Other devices, including smart devices such as lamps, climatecontrol, car components, household components, appliances, etc. may alsobe included in this list.

As used herein, the term “Internet of Things (IoT) device” is used torefer to any object (e.g., an appliance, a sensor, etc.) that has anaddressable interface (e.g., an Internet protocol (IP) address, aBluetooth identifier (ID), a near-field communication (NFC) ID, etc.)and can transmit information to one or more other devices over a wiredor wireless connection. An IoT device may have a passive communicationinterface, such as a quick response (QR) code, a radio-frequencyidentification (RFID) tag, an NFC tag, or the like, or an activecommunication interface, such as a modem, a transceiver, atransmitter-receiver, or the like. An IoT device can have a particularset of attributes (e.g., a device state or status, such as whether theIoT device is on or off, open or closed, idle or active, available fortask execution or busy, and so on, a cooling or heating function, anenvironmental monitoring or recording function, a light-emittingfunction, a sound-emitting function, etc.) that can be embedded inand/or controlled/monitored by a central processing unit (CPU),microprocessor, ASIC, or the like, and configured for connection to anIoT network such as a local ad-hoc network or the Internet. For example,IoT devices may include, but are not limited to, refrigerators,toasters, ovens, microwaves, freezers, dishwashers, dishes, hand tools,clothes washers, clothes dryers, furnaces, air conditioners,thermostats, televisions, light fixtures, vacuum cleaners, sprinklers,electricity meters, gas meters, etc., so long as the devices areequipped with an addressable communications interface for communicatingwith the IoT network. IoT devices may also include cell phones, desktopcomputers, laptop computers, tablet computers, personal digitalassistants (PDAs), etc. Accordingly, the IoT network may be comprised ofa combination of “legacy” Internet-accessible devices (e.g., laptop ordesktop computers, cell phones, etc.) in addition to devices that do nottypically have Internet-connectivity (e.g., dishwashers, etc.).

The user device(s) 120 and/or AP(s) 102 may also include mesh stationsin, for example, a mesh network, in accordance with one or more IEEE802.11 standards and/or 3GPP standards.

Any of the user device(s) 120 (e.g., user devices 124, 126, 128), andAP(s) 102 may be configured to communicate with each other via one ormore communications networks 130 and/or 135 wirelessly or wired. Theuser device(s) 120 may also communicate peer-to-peer or directly witheach other with or without the AP(s) 102. Any of the communicationsnetworks 130 and/or 135 may include, but not limited to, any one of acombination of different types of suitable communications networks suchas, for example, broadcasting networks, cable networks, public networks(e.g., the Internet), private networks, wireless networks, cellularnetworks, or any other suitable private and/or public networks. Further,any of the communications networks 130 and/or 135 may have any suitablecommunication range associated therewith and may include, for example,global networks (e.g., the Internet), metropolitan area networks (MANs),wide area networks (WANs), local area networks (LANs), or personal areanetworks (PANs). In addition, any of the communications networks 130and/or 135 may include any type of medium over which network traffic maybe carried including, but not limited to, coaxial cable, twisted-pairwire, optical fiber, a hybrid fiber coaxial (HFC) medium, microwaveterrestrial transceivers, radio frequency communication mediums, whitespace communication mediums, ultra-high frequency communication mediums,satellite communication mediums, or any combination thereof.

Any of the user device(s) 120 (e.g., user devices 124, 126, 128) andAP(s) 102 may include one or more communications antennas. The one ormore communications antennas may be any suitable type of antennascorresponding to the communications protocols used by the user device(s)120 (e.g., user devices 124, 126 and 128), and AP(s) 102. Somenon-limiting examples of suitable communications antennas include Wi-Fiantennas, Institute of Electrical and Electronics Engineers (IEEE)802.11 family of standards compatible antennas, directional antennas,non-directional antennas, dipole antennas, folded dipole antennas, patchantennas, multiple-input multiple-output (MIMO) antennas,omnidirectional antennas, quasi-omnidirectional antennas, or the like.The one or more communications antennas may be communicatively coupledto a radio component to transmit and/or receive signals, such ascommunications signals to and/or from the user devices 120 and/or AP(s)102.

Any of the user device(s) 120 (e.g., user devices 124, 126, 128), andAP(s) 102 may be configured to perform directional transmission and/ordirectional reception in conjunction with wirelessly communicating in awireless network. Any of the user device(s) 120 (e.g., user devices 124,126, 128), and AP(s) 102 may be configured to perform such directionaltransmission and/or reception using a set of multiple antenna arrays(e.g., DMG antenna arrays or the like). Each of the multiple antennaarrays may be used for transmission and/or reception in a particularrespective direction or range of directions. Any of the user device(s)120 (e.g., user devices 124, 126, 128), and AP(s) 102 may be configuredto perform any given directional transmission towards one or moredefined transmit sectors. Any of the user device(s) 120 (e.g., userdevices 124, 126, 128), and AP(s) 102 may be configured to perform anygiven directional reception from one or more defined receive sectors.

MIMO beamforming in a wireless network may be accomplished using RFbeamforming and/or digital beamforming. In some embodiments, inperforming a given MIMO transmission, user devices 120 and/or AP(s) 102may be configured to use all or a subset of its one or morecommunications antennas to perform MIMO beamforming.

Any of the user devices 120 (e.g., user devices 124, 126, 128), andAP(s) 102 may include any suitable radio and/or transceiver fortransmitting and/or receiving radio frequency (RF) signals in thebandwidth and/or channels corresponding to the communications protocolsutilized by any of the user device(s) 120 and AP(s) 102 to communicatewith each other. The radio components may include hardware and/orsoftware to modulate and/or demodulate communications signals accordingto pre-established transmission protocols. The radio components mayfurther have hardware and/or software instructions to communicate viaone or more Wi-Fi and/or Wi-Fi direct protocols, as standardized by theInstitute of Electrical and Electronics Engineers (IEEE) 802.11standards. In certain example embodiments, the radio component, incooperation with the communications antennas, may be configured tocommunicate via 2.4 GHz channels (e.g. 802.11b, 802.11g, 802.11n,802.11ax), 5 GHz channels (e.g. 802.11n, 802.11ac, 802.11ax, 802.11be,etc.), 6 GHz channels (e.g., 802.11ax, 802.11be, etc.), or 60 GHZchannels (e.g. 802.11ad, 802.11ay). 800 MHz channels (e.g. 802.11ah).The communications antennas may operate at 28 GHz and 40 GHz. It shouldbe understood that this list of communication channels in accordancewith certain 802.11 standards is only a partial list and that other802.11 standards may be used (e.g., Next Generation Wi-Fi, or otherstandards). In some embodiments, non-Wi-Fi protocols may be used forcommunications between devices, such as Bluetooth, dedicated short-rangecommunication (DSRC), Ultra-High Frequency (UHF) (e.g. IEEE 802.11af,IEEE 802.22), white band frequency (e.g., white spaces), or otherpacketized radio communications. The radio component may include anyknown receiver and baseband suitable for communicating via thecommunications protocols. The radio component may further include a lownoise amplifier (LNA), additional signal amplifiers, ananalog-to-digital (A/D) converter, one or more buffers, and digitalbaseband.

In one embodiment, and with reference to FIG. 1 , a user device 120 maybe in communication with one or more APs 102. For example, one or moreAPs 102 may implement a dynamic availability window 142 with one or moreuser devices 120. It is understood that the above descriptions are forpurposes of illustration and are not meant to be limiting.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 2 depicts an illustrative schematic diagram for truncated CSIfeedback, in accordance with one or more example embodiments of thepresent disclosure.

The channel estimates are usually in frequency domain. They can beconverted into time domain by inverse discrete Fourier transform (IDFT)or inverse Fast Fourier Transform (IFFT). If the sampling time of thereceiver is aligned with a multipath delay, i.e., the arrival time ofthe multipath, the multipath is showed up as a single spike in the timedomain channel response as illustrated in the upper portion of FIG. 1 .In general, the sampling time of the receiver is not necessarily alignedwith the multipath delay, i.e., arrival time. In this case, themultipath is showed as a sinc pulse (or filtered sinc pulse) in the timedomain channel response as illustrated in the lower portion of FIG. 2 .In the lower portion of FIG. 2 , the multipath arrives at 0.5 ms insteadof a multiple of 1 ms, i.e., the sampling time. Namely, one reflectionor one multipath in the channel impulse response can spread overmultiple time samples. The reason is that the system is band limited.The decay rate of the tail is l/t, where t is the delay. Namely, thetail is pretty long.

Each sinc pulse has two tails, one at the left and the other at theright of the pulse. Because IDFT or IFFT assumes cyclic operations, thetail ahead of the main peak can show up at the end of the (IFFT) timewindow. The tail showed up at the end of the time window gets truncatedas illustrated in the lower portion of FIG. 2 . This leads to the lossof information. For the example in FIG. 2 , the user receiving thetruncated time domain channel response can't tell whether the channelconsists of one or three major multipaths. In contrast, feeding back allthe time samples solves this problem at the cost of large overhead. Forreducing the overhead, the samples with small pulse tail powers may notneed to be fed back. The user can use multipath estimation techniquessuch as super-resolution algorithms and compressed sensing algorithms todetect the underlying multipaths hidden in the fed back, overlapped, andtruncated sinc pulses. It should be noticed that the lower portion ofFIG. 2 only consists of one multipath instead of multiple ones. Thefeedback receiver is interested in the multipath (e.g., arrival time,magnitude, and phase) not the spread-out since pulse.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 3 depicts an illustrative schematic diagram for truncated CSIfeedback, in accordance with one or more example embodiments of thepresent disclosure.

Referring to FIG. 3 , there is shown the tails of the sinc pulsesinterfere with each other.

Instead of a single multipath, there usually are multiple channelarrivals as illustrated in the upper portion of FIG. 3 . As a result,the tails of the multipaths interfere with each other as illustrated inthe lower portion of FIG. 3 . The user receiving the feedback cannotdetermine the actual number of the multipaths.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 4 depicts an illustrative schematic diagram for truncated CSIfeedback, in accordance with one or more example embodiments of thepresent disclosure.

Referring to FIG. 4 , there are shown feedback samples in the timeinterval.

In one or more embodiments, a truncated CSI feedback system mayfacilitate that the tails ahead of and behind the multipath cluster(s)are needed to be fed back as illustrated in FIG. 4 . Namely, the tail atthe end of the (IFFT) time window should be considered as a wraparoundof the tail ahead of the cluster due to the cyclic operation of IDFT orIFFT. The samples of the tail should be fed back until the tail decaysbelow a certain level or threshold as illustrated in FIG. 4 . Thethreshold may be determined by the noise level or interference plusnoise level or the signal power or the (maximum) peak of the multipath,e.g., 20 dB down from the maximum peak. The threshold may be specifiedin the 802.11 specification, or may be negotiated between the feedbacktransmitter and receiver, or may be specified by the feedbacktransmitter or receiver. A time interval is used. The samples or downsamples, e.g., every 4-, 8-, 16-th samples, in the interval, are fedback. The start time of the time interval may be fed back. The end timeof the time interval or the duration of the time interval may be fedback.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 5 depicts an illustrative schematic diagram for truncated CSIfeedback, in accordance with one or more example embodiments of thepresent disclosure.

Referring to FIG. 5 , there are shown two-time intervals covering twodisjoint channel cluster subsets, respectively.

In one or more embodiments, a truncated CSI feedback system mayfacilitate that if the channel response has multiple clusters apart fromeach other, different time intervals may be used for the disjointsubsets of the channel clusters, respectively, as illustrated in FIG. 5.

In one or more embodiments, since the channel response of eachtransmit-receive antenna pair is different, a different time intervalmay be used for each pair. The different time intervals may be fed back.

In one or more embodiments, to reduce the pulse tail duration, filteringcan be applied. The filtering can increase the decay rate of the pulsetail at the cost of widening the main peak. The filter may be specifiedin the specification or may be indicated in the feedback.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 6 illustrates a flow diagram of illustrative process 600 for atruncated CSI feedback system, in accordance with one or more exampleembodiments of the present disclosure.

At block 602, a device (e.g., the user device(s) 120 and/or the AP 102of FIG. 1 and/or the truncated CSI feedback device 819 of FIG. 8 ) mayestablish a communication link with a station device.

At block 604, the device may identify a feedback frame received from thestation device, wherein the feedback frame comprises informationassociated with channel state information (CSI).

At block 606, the device may identify the feedback frame as one or morefeedback samples.

It is understood that the above descriptions are for purposes ofillustration and are not meant to be limiting.

FIG. 7 shows a functional diagram of an exemplary communication station700, in accordance with one or more example embodiments of the presentdisclosure. In one embodiment, FIG. 7 illustrates a functional blockdiagram of a communication station that may be suitable for use as an AP102 (FIG. 1 ) or a user device 120 (FIG. 1 ) in accordance with someembodiments. The communication station 700 may also be suitable for useas a handheld device, a mobile device, a cellular telephone, asmartphone, a tablet, a netbook, a wireless terminal, a laptop computer,a wearable computer device, a femtocell, a high data rate (HDR)subscriber station, an access point, an access terminal, or otherpersonal communication system (PCS) device.

The communication station 700 may include communications circuitry 702and a transceiver 710 for transmitting and receiving signals to and fromother communication stations using one or more antennas 701. Thecommunications circuitry 702 may include circuitry that can operate thephysical layer (PHY) communications and/or medium access control (MAC)communications for controlling access to the wireless medium, and/or anyother communications layers for transmitting and receiving signals. Thecommunication station 700 may also include processing circuitry 706 andmemory 708 arranged to perform the operations described herein. In someembodiments, the communications circuitry 702 and the processingcircuitry 706 may be configured to perform operations detailed in theabove figures, diagrams, and flows.

In accordance with some embodiments, the communications circuitry 702may be arranged to contend for a wireless medium and configure frames orpackets for communicating over the wireless medium. The communicationscircuitry 702 may be arranged to transmit and receive signals. Thecommunications circuitry 702 may also include circuitry formodulation/demodulation, upconversion/downconversion, filtering,amplification, etc. In some embodiments, the processing circuitry 706 ofthe communication station 700 may include one or more processors. Inother embodiments, two or more antennas 701 may be coupled to thecommunications circuitry 702 arranged for sending and receiving signals.The memory 708 may store information for configuring the processingcircuitry 706 to perform operations for configuring and transmittingmessage frames and performing the various operations described herein.The memory 708 may include any type of memory, including non-transitorymemory, for storing information in a form readable by a machine (e.g., acomputer). For example, the memory 708 may include a computer-readablestorage device, read-only memory (ROM), random-access memory (RAM),magnetic disk storage media, optical storage media, flash-memory devicesand other storage devices and media.

In some embodiments, the communication station 700 may be part of aportable wireless communication device, such as a personal digitalassistant (PDA), a laptop or portable computer with wirelesscommunication capability, a web tablet, a wireless telephone, asmartphone, a wireless headset, a pager, an instant messaging device, adigital camera, an access point, a television, a medical device (e.g., aheart rate monitor, a blood pressure monitor, etc.), a wearable computerdevice, or another device that may receive and/or transmit informationwirelessly.

In some embodiments, the communication station 700 may include one ormore antennas 701. The antennas 701 may include one or more directionalor omnidirectional antennas, including, for example, dipole antennas,monopole antennas, patch antennas, loop antennas, microstrip antennas,or other types of antennas suitable for transmission of RF signals. Insome embodiments, instead of two or more antennas, a single antenna withmultiple apertures may be used. In these embodiments, each aperture maybe considered a separate antenna. In some multiple-input multiple-output(MIMO) embodiments, the antennas may be effectively separated forspatial diversity and the different channel characteristics that mayresult between each of the antennas and the antennas of a transmittingstation.

In some embodiments, the communication station 700 may include one ormore of a keyboard, a display, a non-volatile memory port, multipleantennas, a graphics processor, an application processor, speakers, andother mobile device elements. The display may be an LCD screen includinga touch screen.

Although the communication station 700 is illustrated as having severalseparate functional elements, two or more of the functional elements maybe combined and may be implemented by combinations ofsoftware-configured elements, such as processing elements includingdigital signal processors (DSPs), and/or other hardware elements. Forexample, some elements may include one or more microprocessors, DSPs,field-programmable gate arrays (FPGAs), application specific integratedcircuits (ASICs), radio-frequency integrated circuits (RFICs) andcombinations of various hardware and logic circuitry for performing atleast the functions described herein. In some embodiments, thefunctional elements of the communication station 700 may refer to one ormore processes operating on one or more processing elements.

Certain embodiments may be implemented in one or a combination ofhardware, firmware, and software. Other embodiments may also beimplemented as instructions stored on a computer-readable storagedevice, which may be read and executed by at least one processor toperform the operations described herein. A computer-readable storagedevice may include any non-transitory memory mechanism for storinginformation in a form readable by a machine (e.g., a computer). Forexample, a computer-readable storage device may include read-only memory(ROM), random-access memory (RAM), magnetic disk storage media, opticalstorage media, flash-memory devices, and other storage devices andmedia. In some embodiments, the communication station 700 may includeone or more processors and may be configured with instructions stored ona computer-readable storage device.

FIG. 8 illustrates a block diagram of an example of a machine 800 orsystem upon which any one or more of the techniques (e.g.,methodologies) discussed herein may be performed. In other embodiments,the machine 800 may operate as a standalone device or may be connected(e.g., networked) to other machines. In a networked deployment, themachine 800 may operate in the capacity of a server machine, a clientmachine, or both in server-client network environments. In an example,the machine 800 may act as a peer machine in peer-to-peer (P2P) (orother distributed) network environments. The machine 800 may be apersonal computer (PC), a tablet PC, a set-top box (STB), a personaldigital assistant (PDA), a mobile telephone, a wearable computer device,a web appliance, a network router, a switch or bridge, or any machinecapable of executing instructions (sequential or otherwise) that specifyactions to be taken by that machine, such as a base station. Further,while only a single machine is illustrated, the term “machine” shallalso be taken to include any collection of machines that individually orjointly execute a set (or multiple sets) of instructions to perform anyone or more of the methodologies discussed herein, such as cloudcomputing, software as a service (SaaS), or other computer clusterconfigurations.

Examples, as described herein, may include or may operate on logic or anumber of components, modules, or mechanisms. Modules are tangibleentities (e.g., hardware) capable of performing specified operationswhen operating. A module includes hardware. In an example, the hardwaremay be specifically configured to carry out a specific operation (e.g.,hardwired). In another example, the hardware may include configurableexecution units (e.g., transistors, circuits, etc.) and a computerreadable medium containing instructions where the instructions configurethe execution units to carry out a specific operation when in operation.The configuring may occur under the direction of the executions units ora loading mechanism. Accordingly, the execution units arecommunicatively coupled to the computer-readable medium when the deviceis operating. In this example, the execution units may be a member ofmore than one module. For example, under operation, the execution unitsmay be configured by a first set of instructions to implement a firstmodule at one point in time and reconfigured by a second set ofinstructions to implement a second module at a second point in time.

The machine (e.g., computer system) 800 may include a hardware processor802 (e.g., a central processing unit (CPU), a graphics processing unit(GPU), a hardware processor core, or any combination thereof), a mainmemory 804 and a static memory 806, some or all of which may communicatewith each other via an interlink (e.g., bus) 808. The machine 800 mayfurther include a power management device 832, a graphics display device810, an alphanumeric input device 812 (e.g., a keyboard), and a userinterface (UI) navigation device 814 (e.g., a mouse). In an example, thegraphics display device 810, alphanumeric input device 812, and UInavigation device 814 may be a touch screen display. The machine 800 mayadditionally include a storage device (i.e., drive unit) 816, a signalgeneration device 818 (e.g., a speaker), a truncated CSI feedback device819, a network interface device/transceiver 820 coupled to antenna(s)830, and one or more sensors 828, such as a global positioning system(GPS) sensor, a compass, an accelerometer, or other sensor. The machine800 may include an output controller 834, such as a serial (e.g.,universal serial bus (USB), parallel, or other wired or wireless (e.g.,infrared (IR), near field communication (NFC), etc.) connection tocommunicate with or control one or more peripheral devices (e.g., aprinter, a card reader, etc.)). The operations in accordance with one ormore example embodiments of the present disclosure may be carried out bya baseband processor. The baseband processor may be configured togenerate corresponding baseband signals. The baseband processor mayfurther include physical layer (PHY) and medium access control layer(MAC) circuitry, and may further interface with the hardware processor802 for generation and processing of the baseband signals and forcontrolling operations of the main memory 804, the storage device 816,and/or the truncated CSI feedback device 819. The baseband processor maybe provided on a single radio card, a single chip, or an integratedcircuit (IC).

The storage device 816 may include a machine readable medium 822 onwhich is stored one or more sets of data structures or instructions 824(e.g., software) embodying or utilized by any one or more of thetechniques or functions described herein. The instructions 824 may alsoreside, completely or at least partially, within the main memory 804,within the static memory 806, or within the hardware processor 802during execution thereof by the machine 800. In an example, one or anycombination of the hardware processor 802, the main memory 804, thestatic memory 806, or the storage device 816 may constitutemachine-readable media.

The truncated CSI feedback device 819 may carry out or perform any ofthe operations and processes (e.g., process 600) described and shownabove.

It is understood that the above are only a subset of what the truncatedCSI feedback device 819 may be configured to perform and that otherfunctions included throughout this disclosure may also be performed bythe truncated CSI feedback device 819.

While the machine-readable medium 822 is illustrated as a single medium,the term “machine-readable medium” may include a single medium ormultiple media (e.g., a centralized or distributed database, and/orassociated caches and servers) configured to store the one or moreinstructions 824.

Various embodiments may be implemented fully or partially in softwareand/or firmware. This software and/or firmware may take the form ofinstructions contained in or on a non-transitory computer-readablestorage medium. Those instructions may then be read and executed by oneor more processors to enable performance of the operations describedherein. The instructions may be in any suitable form, such as but notlimited to source code, compiled code, interpreted code, executablecode, static code, dynamic code, and the like. Such a computer-readablemedium may include any tangible non-transitory medium for storinginformation in a form readable by one or more computers, such as but notlimited to read only memory (ROM); random access memory (RAM); magneticdisk storage media; optical storage media; a flash memory, etc.

The term “machine-readable medium” may include any medium that iscapable of storing, encoding, or carrying instructions for execution bythe machine 800 and that cause the machine 800 to perform any one ormore of the techniques of the present disclosure, or that is capable ofstoring, encoding, or carrying data structures used by or associatedwith such instructions. Non-limiting machine-readable medium examplesmay include solid-state memories and optical and magnetic media. In anexample, a massed machine-readable medium includes a machine-readablemedium with a plurality of particles having resting mass. Specificexamples of massed machine-readable media may include non-volatilememory, such as semiconductor memory devices (e.g., electricallyprogrammable read-only memory (EPROM), or electrically erasableprogrammable read-only memory (EEPROM)) and flash memory devices;magnetic disks, such as internal hard disks and removable disks;magneto-optical disks; and CD-ROM and DVD-ROM disks.

The instructions 824 may further be transmitted or received over acommunications network 826 using a transmission medium via the networkinterface device/transceiver 820 utilizing any one of a number oftransfer protocols (e.g., frame relay, internet protocol (IP),transmission control protocol (TCP), user datagram protocol (UDP),hypertext transfer protocol (HTTP), etc.). Example communicationsnetworks may include a local area network (LAN), a wide area network(WAN), a packet data network (e.g., the Internet), mobile telephonenetworks (e.g., cellular networks), plain old telephone (POTS) networks,wireless data networks (e.g., Institute of Electrical and ElectronicsEngineers (IEEE) 802.11 family of standards known as Wi-Fi®, IEEE 802.16family of standards known as WiMax®), IEEE 802.15.4 family of standards,and peer-to-peer (P2P) networks, among others. In an example, thenetwork interface device/transceiver 820 may include one or morephysical jacks (e.g., Ethernet, coaxial, or phone jacks) or one or moreantennas to connect to the communications network 826. In an example,the network interface device/transceiver 820 may include a plurality ofantennas to wirelessly communicate using at least one of single-inputmultiple-output (SIMO), multiple-input multiple-output (MIMO), ormultiple-input single-output (MISO) techniques. The term “transmissionmedium” shall be taken to include any intangible medium that is capableof storing, encoding, or carrying instructions for execution by themachine 800 and includes digital or analog communications signals orother intangible media to facilitate communication of such software.

The operations and processes described and shown above may be carriedout or performed in any suitable order as desired in variousimplementations. Additionally, in certain implementations, at least aportion of the operations may be carried out in parallel. Furthermore,in certain implementations, less than or more than the operationsdescribed may be performed.

FIG. 9 is a block diagram of a radio architecture 105A, 105B inaccordance with some embodiments that may be implemented in any one ofthe example APs 102 and/or the example STAs 120 of FIG. 1 . Radioarchitecture 105A, 105B may include radio front-end module (FEM)circuitry 904 a-b, radio IC circuitry 906 a-b and baseband processingcircuitry 908 a-b. Radio architecture 105A, 105B as shown includes bothWireless Local Area Network (WLAN) functionality and Bluetooth (BT)functionality although embodiments are not so limited. In thisdisclosure, “WLAN” and “Wi-Fi” are used interchangeably.

FEM circuitry 904 a-b may include a WLAN or Wi-Fi FEM circuitry 904 aand a Bluetooth (BT) FEM circuitry 904 b. The WLAN FEM circuitry 904 amay include a receive signal path comprising circuitry configured tooperate on WLAN RF signals received from one or more antennas 901, toamplify the received signals and to provide the amplified versions ofthe received signals to the WLAN radio IC circuitry 906 a for furtherprocessing. The BT FEM circuitry 904 b may include a receive signal pathwhich may include circuitry configured to operate on BT RF signalsreceived from one or more antennas 901, to amplify the received signalsand to provide the amplified versions of the received signals to the BTradio IC circuitry 906 b for further processing. FEM circuitry 904 a mayalso include a transmit signal path which may include circuitryconfigured to amplify WLAN signals provided by the radio IC circuitry906 a for wireless transmission by one or more of the antennas 901. Inaddition, FEM circuitry 904 b may also include a transmit signal pathwhich may include circuitry configured to amplify BT signals provided bythe radio IC circuitry 906 b for wireless transmission by the one ormore antennas. In the embodiment of FIG. 9 , although FEM 904 a and FEM904 b are shown as being distinct from one another, embodiments are notso limited, and include within their scope the use of an FEM (not shown)that includes a transmit path and/or a receive path for both WLAN and BTsignals, or the use of one or more FEM circuitries where at least someof the FEM circuitries share transmit and/or receive signal paths forboth WLAN and BT signals.

Radio IC circuitry 906 a-b as shown may include WLAN radio IC circuitry906 a and BT radio IC circuitry 906 b. The WLAN radio IC circuitry 906 amay include a receive signal path which may include circuitry todown-convert WLAN RF signals received from the FEM circuitry 904 a andprovide baseband signals to WLAN baseband processing circuitry 908 a. BTradio IC circuitry 906 b may in turn include a receive signal path whichmay include circuitry to down-convert BT RF signals received from theFEM circuitry 904 b and provide baseband signals to BT basebandprocessing circuitry 908 b. WLAN radio IC circuitry 906 a may alsoinclude a transmit signal path which may include circuitry to up-convertWLAN baseband signals provided by the WLAN baseband processing circuitry908 a and provide WLAN RF output signals to the FEM circuitry 904 a forsubsequent wireless transmission by the one or more antennas 901. BTradio IC circuitry 906 b may also include a transmit signal path whichmay include circuitry to up-convert BT baseband signals provided by theBT baseband processing circuitry 908 b and provide BT RF output signalsto the FEM circuitry 904 b for subsequent wireless transmission by theone or more antennas 901. In the embodiment of FIG. 9 , although radioIC circuitries 906 a and 906 b are shown as being distinct from oneanother, embodiments are not so limited, and include within their scopethe use of a radio IC circuitry (not shown) that includes a transmitsignal path and/or a receive signal path for both WLAN and BT signals,or the use of one or more radio IC circuitries where at least some ofthe radio IC circuitries share transmit and/or receive signal paths forboth WLAN and BT signals.

Baseband processing circuitry 908 a-b may include a WLAN basebandprocessing circuitry 908 a and a BT baseband processing circuitry 908 b.The WLAN baseband processing circuitry 908 a may include a memory, suchas, for example, a set of RAM arrays in a Fast Fourier Transform orInverse Fast Fourier Transform block (not shown) of the WLAN basebandprocessing circuitry 908 a. Each of the WLAN baseband circuitry 908 aand the BT baseband circuitry 908 b may further include one or moreprocessors and control logic to process the signals received from thecorresponding WLAN or BT receive signal path of the radio IC circuitry906 a-b, and to also generate corresponding WLAN or BT baseband signalsfor the transmit signal path of the radio IC circuitry 906 a-b. Each ofthe baseband processing circuitries 908 a and 908 b may further includephysical layer (PHY) and medium access control layer (MAC) circuitry,and may further interface with a device for generation and processing ofthe baseband signals and for controlling operations of the radio ICcircuitry 906 a-b.

Referring still to FIG. 9 , according to the shown embodiment, WLAN-BTcoexistence circuitry 913 may include logic providing an interfacebetween the WLAN baseband circuitry 908 a and the BT baseband circuitry908 b to enable use cases requiring WLAN and BT coexistence. Inaddition, a switch 903 may be provided between the WLAN FEM circuitry904 a and the BT FEM circuitry 904 b to allow switching between the WLANand BT radios according to application needs. In addition, although theantennas 901 are depicted as being respectively connected to the WLANFEM circuitry 904 a and the BT FEM circuitry 904 b, embodiments includewithin their scope the sharing of one or more antennas as between theWLAN and BT FEMs, or the provision of more than one antenna connected toeach of FEM 904 a or 904 b.

In some embodiments, the front-end module circuitry 904 a-b, the radioIC circuitry 906 a-b, and baseband processing circuitry 908 a-b may beprovided on a single radio card, such as wireless radio card 902. Insome other embodiments, the one or more antennas 901, the FEM circuitry904 a-b and the radio IC circuitry 906 a-b may be provided on a singleradio card. In some other embodiments, the radio IC circuitry 906 a-band the baseband processing circuitry 908 a-b may be provided on asingle chip or integrated circuit (IC), such as IC 912.

In some embodiments, the wireless radio card 902 may include a WLANradio card and may be configured for Wi-Fi communications, although thescope of the embodiments is not limited in this respect. In some ofthese embodiments, the radio architecture 105A, 105B may be configuredto receive and transmit orthogonal frequency division multiplexed (OFDM)or orthogonal frequency division multiple access (OFDMA) communicationsignals over a multicarrier communication channel. The OFDM or OFDMAsignals may comprise a plurality of orthogonal subcarriers.

In some of these multicarrier embodiments, radio architecture 105A, 105Bmay be part of a Wi-Fi communication station (STA) such as a wirelessaccess point (AP), a base station or a mobile device including a Wi-Fidevice. In some of these embodiments, radio architecture 105A, 105B maybe configured to transmit and receive signals in accordance withspecific communication standards and/or protocols, such as any of theInstitute of Electrical and Electronics Engineers (IEEE) standardsincluding, 802.11n-2009, IEEE 802.11-2012, IEEE 802.11-2016,802.11n-2009, 802.11ac, 802.11ah, 802.11ad, 802.11ay and/or 802.11axstandards and/or proposed specifications for WLANs, although the scopeof embodiments is not limited in this respect. Radio architecture 105A,105B may also be suitable to transmit and/or receive communications inaccordance with other techniques and standards.

In some embodiments, the radio architecture 105A, 105B may be configuredfor high-efficiency Wi-Fi (HEW) communications in accordance with theIEEE 802.11ax standard. In these embodiments, the radio architecture105A, 105B may be configured to communicate in accordance with an OFDMAtechnique, although the scope of the embodiments is not limited in thisrespect.

In some other embodiments, the radio architecture 105A, 105B may beconfigured to transmit and receive signals transmitted using one or moreother modulation techniques such as spread spectrum modulation (e.g.,direct sequence code division multiple access (DS-CDMA) and/or frequencyhopping code division multiple access (FH-CDMA)), time-divisionmultiplexing (TDM) modulation, and/or frequency-division multiplexing(FDM) modulation, although the scope of the embodiments is not limitedin this respect.

In some embodiments, as further shown in FIG. 6 , the BT basebandcircuitry 908 b may be compliant with a Bluetooth (BT) connectivitystandard such as Bluetooth, Bluetooth 8.0 or Bluetooth 6.0, or any otheriteration of the Bluetooth Standard.

In some embodiments, the radio architecture 105A, 105B may include otherradio cards, such as a cellular radio card configured for cellular(e.g., 5GPP such as LTE, LTE-Advanced or 7G communications).

In some IEEE 802.11 embodiments, the radio architecture 105A, 105B maybe configured for communication over various channel bandwidthsincluding bandwidths having center frequencies of about 900 MHz, 2.4GHz, 5 GHz, and bandwidths of about 2 MHz, 4 MHz, 5 MHz, 5.5 MHz, 6 MHz,8 MHz, 10 MHz, 20 MHz, 40 MHz, 80 MHz (with contiguous bandwidths) or80+80 MHz (160 MHz) (with non-contiguous bandwidths). In someembodiments, a 920 MHz channel bandwidth may be used. The scope of theembodiments is not limited with respect to the above center frequencieshowever.

FIG. 10 illustrates WLAN FEM circuitry 904 a in accordance with someembodiments. Although the example of FIG. 10 is described in conjunctionwith the WLAN FEM circuitry 904 a, the example of FIG. 10 may bedescribed in conjunction with the example BT FEM circuitry 904 b (FIG. 9), although other circuitry configurations may also be suitable.

In some embodiments, the FEM circuitry 904 a may include a TX/RX switch1002 to switch between transmit mode and receive mode operation. The FEMcircuitry 904 a may include a receive signal path and a transmit signalpath. The receive signal path of the FEM circuitry 904 a may include alow-noise amplifier (LNA) 1006 to amplify received RF signals 1003 andprovide the amplified received RF signals 1007 as an output (e.g., tothe radio IC circuitry 906 a-b (FIG. 9 )). The transmit signal path ofthe circuitry 904 a may include a power amplifier (PA) to amplify inputRF signals 1009 (e.g., provided by the radio IC circuitry 906 a-b), andone or more filters 1012, such as band-pass filters (BPFs), low-passfilters (LPFs) or other types of filters, to generate RF signals 1015for subsequent transmission (e.g., by one or more of the antennas 901(FIG. 9 )) via an example duplexer 1014.

In some dual-mode embodiments for Wi-Fi communication, the FEM circuitry904 a may be configured to operate in either the 2.4 GHz frequencyspectrum or the 5 GHz frequency spectrum. In these embodiments, thereceive signal path of the FEM circuitry 904 a may include a receivesignal path duplexer 1004 to separate the signals from each spectrum aswell as provide a separate LNA 1006 for each spectrum as shown. In theseembodiments, the transmit signal path of the FEM circuitry 904 a mayalso include a power amplifier 1010 and a filter 1012, such as a BPF, anLPF or another type of filter for each frequency spectrum and a transmitsignal path duplexer 1004 to provide the signals of one of the differentspectrums onto a single transmit path for subsequent transmission by theone or more of the antennas 901 (FIG. 9 ). In some embodiments, BTcommunications may utilize the 2.4 GHz signal paths and may utilize thesame FEM circuitry 904 a as the one used for WLAN communications.

FIG. 11 illustrates radio IC circuitry 906 a in accordance with someembodiments. The radio IC circuitry 906 a is one example of circuitrythat may be suitable for use as the WLAN or BT radio IC circuitry 906a/906 b (FIG. 9 ), although other circuitry configurations may also besuitable. Alternatively, the example of FIG. 11 may be described inconjunction with the example BT radio IC circuitry 906 b.

In some embodiments, the radio IC circuitry 906 a may include a receivesignal path and a transmit signal path. The receive signal path of theradio IC circuitry 906 a may include at least mixer circuitry 1102, suchas, for example, down-conversion mixer circuitry, amplifier circuitry1106 and filter circuitry 1108. The transmit signal path of the radio ICcircuitry 906 a may include at least filter circuitry 1112 and mixercircuitry 1114, such as, for example, up-conversion mixer circuitry.Radio IC circuitry 906 a may also include synthesizer circuitry 1104 forsynthesizing a frequency 1105 for use by the mixer circuitry 1102 andthe mixer circuitry 1114. The mixer circuitry 1102 and/or 1114 may each,according to some embodiments, be configured to provide directconversion functionality. The latter type of circuitry presents a muchsimpler architecture as compared with standard super-heterodyne mixercircuitries, and any flicker noise brought about by the same may bealleviated for example through the use of OFDM modulation. FIG. 11illustrates only a simplified version of a radio IC circuitry, and mayinclude, although not shown, embodiments where each of the depictedcircuitries may include more than one component. For instance, mixercircuitry 1114 may each include one or more mixers, and filtercircuitries 1108 and/or 1112 may each include one or more filters, suchas one or more BPFs and/or LPFs according to application needs. Forexample, when mixer circuitries are of the direct-conversion type, theymay each include two or more mixers.

In some embodiments, mixer circuitry 1102 may be configured todown-convert RF signals 1007 received from the FEM circuitry 904 a-b(FIG. 9 ) based on the synthesized frequency 1105 provided bysynthesizer circuitry 1104. The amplifier circuitry 1106 may beconfigured to amplify the down-converted signals and the filtercircuitry 1108 may include an LPF configured to remove unwanted signalsfrom the down-converted signals to generate output baseband signals1107. Output baseband signals 1107 may be provided to the basebandprocessing circuitry 908 a-b (FIG. 9 ) for further processing. In someembodiments, the output baseband signals 1107 may be zero-frequencybaseband signals, although this is not a requirement. In someembodiments, mixer circuitry 1102 may comprise passive mixers, althoughthe scope of the embodiments is not limited in this respect.

In some embodiments, the mixer circuitry 1114 may be configured toup-convert input baseband signals 1111 based on the synthesizedfrequency 1105 provided by the synthesizer circuitry 1104 to generate RFoutput signals 1009 for the FEM circuitry 904 a-b. The baseband signals1111 may be provided by the baseband processing circuitry 908 a-b andmay be filtered by filter circuitry 1112. The filter circuitry 1112 mayinclude an LPF or a BPF, although the scope of the embodiments is notlimited in this respect.

In some embodiments, the mixer circuitry 1102 and the mixer circuitry1114 may each include two or more mixers and may be arranged forquadrature down-conversion and/or up-conversion respectively with thehelp of synthesizer 1104. In some embodiments, the mixer circuitry 1102and the mixer circuitry 1114 may each include two or more mixers eachconfigured for image rejection (e.g., Hartley image rejection). In someembodiments, the mixer circuitry 1102 and the mixer circuitry 1114 maybe arranged for direct down-conversion and/or direct up-conversion,respectively. In some embodiments, the mixer circuitry 1102 and themixer circuitry 1114 may be configured for super-heterodyne operation,although this is not a requirement.

Mixer circuitry 1102 may comprise, according to one embodiment:quadrature passive mixers (e.g., for the in-phase (I) and quadraturephase (Q) paths). In such an embodiment, RF input signal 1007 from FIG.11 may be down-converted to provide I and Q baseband output signals tobe sent to the baseband processor.

Quadrature passive mixers may be driven by zero and ninety-degreetime-varying LO switching signals provided by a quadrature circuitrywhich may be configured to receive a LO frequency (fLO) from a localoscillator or a synthesizer, such as LO frequency 1105 of synthesizer1104 (FIG. 11 ). In some embodiments, the LO frequency may be thecarrier frequency, while in other embodiments, the LO frequency may be afraction of the carrier frequency (e.g., one-half the carrier frequency,one-third the carrier frequency). In some embodiments, the zero andninety-degree time-varying switching signals may be generated by thesynthesizer, although the scope of the embodiments is not limited inthis respect.

In some embodiments, the LO signals may differ in duty cycle (thepercentage of one period in which the LO signal is high) and/or offset(the difference between start points of the period). In someembodiments, the LO signals may have an 85% duty cycle and an 80%offset. In some embodiments, each branch of the mixer circuitry (e.g.,the in-phase (I) and quadrature phase (Q) path) may operate at an 80%duty cycle, which may result in a significant reduction is powerconsumption.

The RF input signal 1007 (FIG. 10 ) may comprise a balanced signal,although the scope of the embodiments is not limited in this respect.The I and Q baseband output signals may be provided to low-noiseamplifier, such as amplifier circuitry 1106 (FIG. 11 ) or to filtercircuitry 1108 (FIG. 11 ).

In some embodiments, the output baseband signals 1107 and the inputbaseband signals 1111 may be analog baseband signals, although the scopeof the embodiments is not limited in this respect. In some alternateembodiments, the output baseband signals 1107 and the input basebandsignals 1111 may be digital baseband signals. In these alternateembodiments, the radio IC circuitry may include analog-to-digitalconverter (ADC) and digital-to-analog converter (DAC) circuitry.

In some dual-mode embodiments, a separate radio IC circuitry may beprovided for processing signals for each spectrum, or for otherspectrums not mentioned here, although the scope of the embodiments isnot limited in this respect.

In some embodiments, the synthesizer circuitry 1104 may be afractional-N synthesizer or a fractional N/N+1 synthesizer, although thescope of the embodiments is not limited in this respect as other typesof frequency synthesizers may be suitable. For example, synthesizercircuitry 1104 may be a delta-sigma synthesizer, a frequency multiplier,or a synthesizer comprising a phase-locked loop with a frequencydivider. According to some embodiments, the synthesizer circuitry 1104may include digital synthesizer circuitry. An advantage of using adigital synthesizer circuitry is that, although it may still includesome analog components, its footprint may be scaled down much more thanthe footprint of an analog synthesizer circuitry. In some embodiments,frequency input into synthesizer circuitry 1104 may be provided by avoltage controlled oscillator (VCO), although that is not a requirement.A divider control input may further be provided by either the basebandprocessing circuitry 908 a-b (FIG. 9 ) depending on the desired outputfrequency 1105. In some embodiments, a divider control input (e.g., N)may be determined from a look-up table (e.g., within a Wi-Fi card) basedon a channel number and a channel center frequency as determined orindicated by the example application processor 910. The applicationprocessor 910 may include, or otherwise be connected to, one of theexample secure signal converter 101 or the example received signalconverter 103 (e.g., depending on which device the example radioarchitecture is implemented in).

In some embodiments, synthesizer circuitry 1104 may be configured togenerate a carrier frequency as the output frequency 1105, while inother embodiments, the output frequency 1105 may be a fraction of thecarrier frequency (e.g., one-half the carrier frequency, one-third thecarrier frequency). In some embodiments, the output frequency 1105 maybe a LO frequency (fLO).

FIG. 12 illustrates a functional block diagram of baseband processingcircuitry 908 a in accordance with some embodiments. The basebandprocessing circuitry 908 a is one example of circuitry that may besuitable for use as the baseband processing circuitry 908 a (FIG. 9 ),although other circuitry configurations may also be suitable.Alternatively, the example of FIG. 11 may be used to implement theexample BT baseband processing circuitry 908 b of FIG. 9 .

The baseband processing circuitry 908 a may include a receive basebandprocessor (RX BBP) 1202 for processing receive baseband signals 1109provided by the radio IC circuitry 906 a-b (FIG. 9 ) and a transmitbaseband processor (TX BBP) 1204 for generating transmit basebandsignals 1111 for the radio IC circuitry 906 a-b. The baseband processingcircuitry 908 a may also include control logic 1206 for coordinating theoperations of the baseband processing circuitry 908 a.

In some embodiments (e.g., when analog baseband signals are exchangedbetween the baseband processing circuitry 908 a-b and the radio ICcircuitry 906 a-b), the baseband processing circuitry 908 a may includeADC 1210 to convert analog baseband signals 1209 received from the radioIC circuitry 906 a-b to digital baseband signals for processing by theRX BBP 1202. In these embodiments, the baseband processing circuitry 908a may also include DAC 1212 to convert digital baseband signals from theTX BBP 1204 to analog baseband signals 1211.

In some embodiments that communicate OFDM signals or OFDMA signals, suchas through baseband processor 908 a, the transmit baseband processor1204 may be configured to generate OFDM or OFDMA signals as appropriatefor transmission by performing an inverse fast Fourier transform (IFFT).The receive baseband processor 1202 may be configured to processreceived OFDM signals or OFDMA signals by performing an FFT. In someembodiments, the receive baseband processor 1202 may be configured todetect the presence of an OFDM signal or OFDMA signal by performing anautocorrelation, to detect a preamble, such as a short preamble, and byperforming a cross-correlation, to detect a long preamble. The preamblesmay be part of a predetermined frame structure for Wi-Fi communication.

Referring back to FIG. 9 , in some embodiments, the antennas 901 (FIG. 9) may each comprise one or more directional or omnidirectional antennas,including, for example, dipole antennas, monopole antennas, patchantennas, loop antennas, microstrip antennas or other types of antennassuitable for transmission of RF signals. In some multiple-inputmultiple-output (MIMO) embodiments, the antennas may be effectivelyseparated to take advantage of spatial diversity and the differentchannel characteristics that may result. Antennas 901 may each include aset of phased-array antennas, although embodiments are not so limited.

Although the radio architecture 105A, 105B is illustrated as havingseveral separate functional elements, one or more of the functionalelements may be combined and may be implemented by combinations ofsoftware-configured elements, such as processing elements includingdigital signal processors (DSPs), and/or other hardware elements. Forexample, some elements may comprise one or more microprocessors, DSPs,field-programmable gate arrays (FPGAs), application specific integratedcircuits (ASICs), radio-frequency integrated circuits (RFICs) andcombinations of various hardware and logic circuitry for performing atleast the functions described herein. In some embodiments, thefunctional elements may refer to one or more processes operating on oneor more processing elements.

The word “exemplary” is used herein to mean “serving as an example,instance, or illustration.” Any embodiment described herein as“exemplary” is not necessarily to be construed as preferred oradvantageous over other embodiments. The terms “computing device,” “userdevice,” “communication station,” “station,” “handheld device,” “mobiledevice,” “wireless device” and “user equipment” (UE) as used hereinrefers to a wireless communication device such as a cellular telephone,a smartphone, a tablet, a netbook, a wireless terminal, a laptopcomputer, a femtocell, a high data rate (HDR) subscriber station, anaccess point, a printer, a point of sale device, an access terminal, orother personal communication system (PCS) device. The device may beeither mobile or stationary.

As used within this document, the term “communicate” is intended toinclude transmitting, or receiving, or both transmitting and receiving.This may be particularly useful in claims when describing theorganization of data that is being transmitted by one device andreceived by another, but only the functionality of one of those devicesis required to infringe the claim. Similarly, the bidirectional exchangeof data between two devices (both devices transmit and receive duringthe exchange) may be described as “communicating,” when only thefunctionality of one of those devices is being claimed. The term“communicating” as used herein with respect to a wireless communicationsignal includes transmitting the wireless communication signal and/orreceiving the wireless communication signal. For example, a wirelesscommunication unit, which is capable of communicating a wirelesscommunication signal, may include a wireless transmitter to transmit thewireless communication signal to at least one other wirelesscommunication unit, and/or a wireless communication receiver to receivethe wireless communication signal from at least one other wirelesscommunication unit.

As used herein, unless otherwise specified, the use of the ordinaladjectives “first,” “second,” “third,” etc., to describe a commonobject, merely indicates that different instances of like objects arebeing referred to and are not intended to imply that the objects sodescribed must be in a given sequence, either temporally, spatially, inranking, or in any other manner.

The term “access point” (AP) as used herein may be a fixed station. Anaccess point may also be referred to as an access node, a base station,an evolved node B (eNodeB), or some other similar terminology known inthe art. An access terminal may also be called a mobile station, userequipment (UE), a wireless communication device, or some other similarterminology known in the art. Embodiments disclosed herein generallypertain to wireless networks. Some embodiments may relate to wirelessnetworks that operate in accordance with one of the IEEE 802.11standards.

Some embodiments may be used in conjunction with various devices andsystems, for example, a personal computer (PC), a desktop computer, amobile computer, a laptop computer, a notebook computer, a tabletcomputer, a server computer, a handheld computer, a handheld device, apersonal digital assistant (PDA) device, a handheld PDA device, anon-board device, an off-board device, a hybrid device, a vehiculardevice, a non-vehicular device, a mobile or portable device, a consumerdevice, a non-mobile or non-portable device, a wireless communicationstation, a wireless communication device, a wireless access point (AP),a wired or wireless router, a wired or wireless modem, a video device,an audio device, an audio-video (A/V) device, a wired or wirelessnetwork, a wireless area network, a wireless video area network (WVAN),a local area network (LAN), a wireless LAN (WLAN), a personal areanetwork (PAN), a wireless PAN (WPAN), and the like.

Some embodiments may be used in conjunction with one way and/or two-wayradio communication systems, cellular radio-telephone communicationsystems, a mobile phone, a cellular telephone, a wireless telephone, apersonal communication system (PCS) device, a PDA device whichincorporates a wireless communication device, a mobile or portableglobal positioning system (GPS) device, a device which incorporates aGPS receiver or transceiver or chip, a device which incorporates an RFIDelement or chip, a multiple input multiple output (MIMO) transceiver ordevice, a single input multiple output (SIMO) transceiver or device, amultiple input single output (MISO) transceiver or device, a devicehaving one or more internal antennas and/or external antennas, digitalvideo broadcast (DVB) devices or systems, multi-standard radio devicesor systems, a wired or wireless handheld device, e.g., a smartphone, awireless application protocol (WAP) device, or the like.

Some embodiments may be used in conjunction with one or more types ofwireless communication signals and/or systems following one or morewireless communication protocols, for example, radio frequency (RF),infrared (IR), frequency-division multiplexing (FDM), orthogonal FDM(OFDM), time-division multiplexing (TDM), time-division multiple access(TDMA), extended TDMA (E-TDMA), general packet radio service (GPRS),extended GPRS, code-division multiple access (CDMA), wideband CDMA(WCDMA), CDMA 2000, single-carrier CDMA, multi-carrier CDMA,multi-carrier modulation (MDM), discrete multi-tone (DMT), Bluetooth®,global positioning system (GPS), Wi-Fi, Wi-Max, ZigBee, ultra-wideband(UWB), global system for mobile communications (GSM), 2G, 2.5G, 3G,3.5G, 4G, fifth generation (5G) mobile networks, 3GPP, long termevolution (LTE), LTE advanced, enhanced data rates for GSM Evolution(EDGE), or the like. Other embodiments may be used in various otherdevices, systems, and/or networks.

The following examples pertain to further embodiments.

Example 1 may include a device comprising processing circuitry coupledto storage, the processing circuitry configured to: establish acommunication link with a station device; identify a feedback framereceived from the station device, wherein the feedback frame comprisesinformation associated with channel state information (CSI); andidentify the feedback frame as one or more feedback samples.

Example 2 may include the device of example 1 and/or some other exampleherein, wherein the one or more feedback samples are sampled every 4, 8,16 samples.

Example 3 may include the device of example 1 and/or some other exampleherein, wherein wherein the one or more feedback samples are receivedduring one or more time interval.

Example 4 may include the device of example 1 and/or some other exampleherein, wherein the feedback frame comprises a tail.

Example 5 may include the device of example 4 and/or some other exampleherein, wherein wherein the tail may be at an end of an inverse FastFourier Transform (IFFT) time window.

Example 6 may include the device of example 4 and/or some other exampleherein, wherein the tail may be considered as a wraparound of a secondtail ahead of a cluster.

Example 7 may include the device of example 4 and/or some other exampleherein, wherein the tail may be fed back until the tail decays below athreshold.

Example 8 may include the device of example 7 and/or some other exampleherein, wherein the threshold may be determined by a noise level, aninterference, a signal power, or a peak of a multipath associated withthe communication link.

Example 9 may include the device of example 1 and/or some other exampleherein, further comprising a transceiver configured to transmit andreceive wireless signals.

Example 10 may include the device of example 8 and/or some other exampleherein, further comprising an antenna coupled to the transceiver tocause to send the feedback frame.

Example 11 may include a non-transitory computer-readable medium storingcomputer-executable instructions which when executed by one or moreprocessors result in performing operations comprising: establishing acommunication link with a station device; identifying a feedback framereceived from the station device, wherein the feedback frame comprisesinformation associated with channel state information (CSI); andidentifying the feedback frame as one or more feedback samples.

Example 12 may include the non-transitory computer-readable medium ofexample 11 and/or some other example herein, wherein the one or morefeedback samples are sampled every 4, 8, 16 samples.

Example 13 may include the non-transitory computer-readable medium ofexample 11 and/or some other example herein, wherein wherein the one ormore feedback samples are received during one or more time interval.

Example 14 may include the non-transitory computer-readable medium ofexample 11 and/or some other example herein, wherein the feedback framecomprises a tail.

Example 15 may include the non-transitory computer-readable medium ofexample 14 and/or some other example herein, wherein wherein the tailmay be at an end of an inverse Fast Fourier Transform (IFFT) timewindow.

Example 16 may include the non-transitory computer-readable medium ofexample 14 and/or some other example herein, wherein the tail may beconsidered as a wraparound of a second tail ahead of a cluster.

Example 17 may include the non-transitory computer-readable medium ofexample 14 and/or some other example herein, wherein the tail may be fedback until the tail decays below a threshold.

Example 18 may include the non-transitory computer-readable medium ofexample 17 and/or some other example herein, wherein the threshold maybe determined by a noise level, an interference, a signal power, or apeak of a multipath associated with the communication link.

Example 19 may include a method comprising: establishing, by one or moreprocessors, a communication link with a station device; identifying afeedback frame received from the station device, wherein the feedbackframe comprises information associated with channel state information(CSI); and identifying the feedback frame as one or more feedbacksamples.

Example 20 may include the method of example 19 and/or some otherexample herein, wherein the one or more feedback samples are sampledevery 4, 8, 16 samples.

Example 21 may include the method of example 19 and/or some otherexample herein, wherein wherein the one or more feedback samples arereceived during one or more time interval.

Example 22 may include the method of example 19 and/or some otherexample herein, wherein the feedback frame comprises a tail.

Example 23 may include the method of example 22 and/or some otherexample herein, wherein wherein the tail may be at an end of an inverseFast Fourier Transform (IFFT) time window.

Example 24 may include the method of example 22 and/or some otherexample herein, wherein the tail may be considered as a wraparound of asecond tail ahead of a cluster.

Example 25 may include the method of example 22 and/or some otherexample herein, wherein the tail may be fed back until the tail decaysbelow a threshold.

Example 26 may include the method of example 25 and/or some otherexample herein, wherein the threshold may be determined by a noiselevel, an interference, a signal power, or a peak of a multipathassociated with the communication link.

Example 27 may include an apparatus comprising means for: establishing acommunication link with a station device; identifying a feedback framereceived from the station device, wherein the feedback frame comprisesinformation associated with channel state information (CSI); andidentifying the feedback frame as one or more feedback samples.

Example 28 may include the apparatus of example 27 and/or some otherexample herein, wherein the one or more feedback samples are sampledevery 4, 8, 16 samples.

Example 29 may include the apparatus of example 27 and/or some otherexample herein, wherein wherein the one or more feedback samples arereceived during one or more time interval.

Example 30 may include the apparatus of example 27 and/or some otherexample herein, wherein the feedback frame comprises a tail.

Example 31 may include the apparatus of example 30 and/or some otherexample herein, wherein wherein the tail may be at an end of an inverseFast Fourier Transform (IFFT) time window.

Example 32 may include the apparatus of example 30 and/or some otherexample herein, wherein the tail may be considered as a wraparound of asecond tail ahead of a cluster.

Example 33 may include the apparatus of example 30 and/or some otherexample herein, wherein the tail may be fed back until the tail decaysbelow a threshold.

Example 34 may include the apparatus of example 33 and/or some otherexample herein, wherein the threshold may be determined by a noiselevel, an interference, a signal power, or a peak of a multipathassociated with the communication link.

Example 35 may include one or more non-transitory computer-readablemedia comprising instructions to cause an electronic device, uponexecution of the instructions by one or more processors of theelectronic device, to perform one or more elements of a method describedin or related to any of examples 1-34, or any other method or processdescribed herein.

Example 36 may include an apparatus comprising logic, modules, and/orcircuitry to perform one or more elements of a method described in orrelated to any of examples 1-34, or any other method or processdescribed herein.

Example 37 may include a method, technique, or process as described inor related to any of examples 1-34, or portions or parts thereof.

Example 38 may include an apparatus comprising: one or more processorsand one or more computer readable media comprising instructions that,when executed by the one or more processors, cause the one or moreprocessors to perform the method, techniques, or process as described inor related to any of examples 1-34, or portions thereof.

Example 39 may include a method of communicating in a wireless networkas shown and described herein.

Example 40 may include a system for providing wireless communication asshown and described herein.

Example 41 may include a device for providing wireless communication asshown and described herein.

Embodiments according to the disclosure are in particular disclosed inthe attached claims directed to a method, a storage medium, a device anda computer program product, wherein any feature mentioned in one claimcategory, e.g., method, can be claimed in another claim category, e.g.,system, as well. The dependencies or references back in the attachedclaims are chosen for formal reasons only. However, any subject matterresulting from a deliberate reference back to any previous claims (inparticular multiple dependencies) can be claimed as well, so that anycombination of claims and the features thereof are disclosed and can beclaimed regardless of the dependencies chosen in the attached claims.The subject-matter which can be claimed comprises not only thecombinations of features as set out in the attached claims but also anyother combination of features in the claims, wherein each featurementioned in the claims can be combined with any other feature orcombination of other features in the claims. Furthermore, any of theembodiments and features described or depicted herein can be claimed ina separate claim and/or in any combination with any embodiment orfeature described or depicted herein or with any of the features of theattached claims.

The foregoing description of one or more implementations providesillustration and description, but is not intended to be exhaustive or tolimit the scope of embodiments to the precise form disclosed.Modifications and variations are possible in light of the aboveteachings or may be acquired from practice of various embodiments.

Certain aspects of the disclosure are described above with reference toblock and flow diagrams of systems, methods, apparatuses, and/orcomputer program products according to various implementations. It willbe understood that one or more blocks of the block diagrams and flowdiagrams, and combinations of blocks in the block diagrams and the flowdiagrams, respectively, may be implemented by computer-executableprogram instructions. Likewise, some blocks of the block diagrams andflow diagrams may not necessarily need to be performed in the orderpresented, or may not necessarily need to be performed at all, accordingto some implementations.

These computer-executable program instructions may be loaded onto aspecial-purpose computer or other particular machine, a processor, orother programmable data processing apparatus to produce a particularmachine, such that the instructions that execute on the computer,processor, or other programmable data processing apparatus create meansfor implementing one or more functions specified in the flow diagramblock or blocks. These computer program instructions may also be storedin a computer-readable storage media or memory that may direct acomputer or other programmable data processing apparatus to function ina particular manner, such that the instructions stored in thecomputer-readable storage media produce an article of manufactureincluding instruction means that implement one or more functionsspecified in the flow diagram block or blocks. As an example, certainimplementations may provide for a computer program product, comprising acomputer-readable storage medium having a computer-readable program codeor program instructions implemented therein, said computer-readableprogram code adapted to be executed to implement one or more functionsspecified in the flow diagram block or blocks. The computer programinstructions may also be loaded onto a computer or other programmabledata processing apparatus to cause a series of operational elements orsteps to be performed on the computer or other programmable apparatus toproduce a computer-implemented process such that the instructions thatexecute on the computer or other programmable apparatus provide elementsor steps for implementing the functions specified in the flow diagramblock or blocks.

Accordingly, blocks of the block diagrams and flow diagrams supportcombinations of means for performing the specified functions,combinations of elements or steps for performing the specified functionsand program instruction means for performing the specified functions. Itwill also be understood that each block of the block diagrams and flowdiagrams, and combinations of blocks in the block diagrams and flowdiagrams, may be implemented by special-purpose, hardware-based computersystems that perform the specified functions, elements or steps, orcombinations of special-purpose hardware and computer instructions.

Conditional language, such as, among others, “can,” “could,” “might,” or“may,” unless specifically stated otherwise, or otherwise understoodwithin the context as used, is generally intended to convey that certainimplementations could include, while other implementations do notinclude, certain features, elements, and/or operations. Thus, suchconditional language is not generally intended to imply that features,elements, and/or operations are in any way required for one or moreimplementations or that one or more implementations necessarily includelogic for deciding, with or without user input or prompting, whetherthese features, elements, and/or operations are included or are to beperformed in any particular implementation.

Many modifications and other implementations of the disclosure set forthherein will be apparent having the benefit of the teachings presented inthe foregoing descriptions and the associated drawings. Therefore, it isto be understood that the disclosure is not to be limited to thespecific implementations disclosed and that modifications and otherimplementations are intended to be included within the scope of theappended claims. Although specific terms are employed herein, they areused in a generic and descriptive sense only and not for purposes oflimitation.

What is claimed is:
 1. A device, the device comprising processingcircuitry coupled to storage, the processing circuitry configured to:establish a communication link with a station device; identify afeedback frame received from the station device, wherein the feedbackframe comprises information associated with channel state information(CSI); and identify the feedback frame as one or more feedback samples.2. The device of claim 1, wherein the one or more feedback samples aresampled every 4, 8, 16 samples.
 3. The device of claim 1, whereinwherein the one or more feedback samples are received during one or moretime interval.
 4. The device of claim 1, wherein the feedback framecomprises a tail.
 5. The device of claim 4, wherein wherein the tail isat an end of an inverse Fast Fourier Transform (IFFT) time window. 6.The device of claim 4, wherein the tail is considered as a wraparound ofa second tail ahead of a cluster.
 7. The device of claim 4, wherein thetail is fed back until the tail decays below a threshold.
 8. The deviceof claim 7, wherein the threshold is determined by a noise level, aninterference, a signal power, or a peak of a multipath associated withthe communication link.
 9. The device of claim 1, further comprising atransceiver configured to transmit and receive wireless signals.
 10. Thedevice of claim 8, further comprising an antenna coupled to thetransceiver to cause to send the feedback frame.
 11. A non-transitorycomputer-readable medium storing computer-executable instructions whichwhen executed by one or more processors result in performing operationscomprising: establishing a communication link with a station device;identifying a feedback frame received from the station device, whereinthe feedback frame comprises information associated with channel stateinformation (CSI); and identifying the feedback frame as one or morefeedback samples.
 12. The non-transitory computer-readable medium ofclaim 11, wherein the one or more feedback samples are sampled every 4,8, 16 samples.
 13. The non-transitory computer-readable medium of claim11, wherein wherein the one or more feedback samples are received duringone or more time interval.
 14. The non-transitory computer-readablemedium of claim 11, wherein the feedback frame comprises a tail.
 15. Thenon-transitory computer-readable medium of claim 14, wherein wherein thetail is at an end of an inverse Fast Fourier Transform (IFFT) timewindow.
 16. The non-transitory computer-readable medium of claim 14,wherein the tail is considered as a wraparound of a second tail ahead ofa cluster.
 17. The non-transitory computer-readable medium of claim 14,wherein the tail is fed back until the tail decays below a threshold.18. The non-transitory computer-readable medium of claim 17, wherein thethreshold is determined by a noise level, an interference, a signalpower, or a peak of a multipath associated with the communication link.19. A method comprising: establishing, by one or more processors, acommunication link with a station device; identifying a feedback framereceived from the station device, wherein the feedback frame comprisesinformation associated with channel state information (CSI); andidentifying the feedback frame as one or more feedback samples.
 20. Themethod of claim 19, wherein the one or more feedback samples are sampledevery 4, 8, 16 samples.